Ultrasound scanners provide useful information about the interior characteristics of an object under examination. In medical applications, clinicians have used ultrasound scanners to examine human subjects in settings such as hospitals, physician's offices, and other locations. Ultrasound scanners have been used in the emergency room, operating room, radiology department, patient room, and/or other environments. In use, an acoustic coupling agent, typically a lubricious gel largely composed of water and propylene glycol, is placed on the acoustic window/lens of the ultrasound transducer array and/or an area of the patient in connection with the region of interest to be scanned. The user then positions the transducer array with respect to the area of the patient. The gel between the acoustic window and the area provides an acoustic medium that facilitates transferring ultrasound signals there between. The ultrasound scanner can then be used to scan the region of interest.
In some environments (e.g., sterile environments), transducer covers are used. Transducer covers conventionally have included a rubber or thin plastic bag or sheath that physically surrounds and encloses the entire or a sub-portion of the probe. When a cover is used an acoustic coupling agent is required both between the transducer and cover and between the cover and the patient. Such covers are supplied sterilized in sterile packaging (e.g., U.S. Pat. No. 3,754,700) and may come prefilled with a coupling gel and/or other coupling agent. Other covers are not pre-filled, and the user adds gel into the bag prior installing on the transducer. The user also applies the gel on the outside of the cover and/or on the area of the patient. Other covers have included cup-shaped covers that snap on the probe (e.g., U.S. Pat. No. 6,132,378) and self-adhesive thin pliable film dressings that are wrapped around and adhere to the probe (e.g., U.S. 2006/0264751 A1). Unfortunately, such covers can be cumbersome to install and use.
Procedures such as biopsies, peripheral intravenous insertions (PIVs), and/or other procedures which involve use of a needle entail employing a separate needle guide apparatus with the probe or a needle guide accessory that attaches to the probe. Generally, such needle guides have been configured to constrain a needle in a fixed path (plane and/or insertion angle), for example, that is in the middle of elevation of the acoustic beam (traditional single plane transducer) represented by a guide line on the ultrasound system. A typical needle guide has two main components: a reusable bracket that snaps on the probe and is placed under the cover (where a cover is used), and a disposable guide that attaches from outside the cover. Unfortunately, such assembly may not be easy to install and may require more than one person to maintain sterility during cover and/or needle guide installation in a sterile environment, and may be too restrictive for PIV. Furthermore, for certain procedures such as peripheral intravenous insertions, the size of the sterile field is limited to a small area directly around the insertion site and a cover that encloses the entire transducer may provide more coverage than is required. Moreover, traditional ultrasound gel is not well-suited for ultrasound guided peripheral intravenous insertions, for example, because of post needle insertion cleanup in preparation for application of dressings over the catheter.